Wire size to connect to K&T to extend wires?


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Old 02-26-14, 06:58 AM
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Wire size to connect to K&T to extend wires?

i have an old house with K&T. I need to extend it to a new service panel (just lights and plugs). It's not practical to replace all of it with romex and the K&T is in very good shape. I know K&T has higher amperage. What size romex should I use? Can I use 14/2? What does CA electrical code require? Thank you!!
 
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Old 02-26-14, 08:20 AM
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Knob and tube circuits cannot be extended. Also, a service panel is a source of power, often called the main panel.

Most K&T wiring was done with #14 conductors, limited to a 15 ampere fuse or circuit breaker.
 
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Old 02-26-14, 09:24 AM
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I've installed a csed. I understand you can wire nut K&T in a plastic JB into Romex should I use 14 or 12 for lights and plugs?
 
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Old 02-26-14, 09:30 AM
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I have no idea what a csed may be. You will need to protect the K&T conductors with additional loom where they enter the junction box and they need to be clamped to prevent them from coming out. For this reason a steel box with loom clamps may be better than a plastic box. Use #14 type NM cable and protect with a 15 ampere circuit breaker.
 
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Old 02-26-14, 10:03 AM
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As Furd said what you want to is not code compliant because K&T shouldn't be extended. In addition it is unsafe and not code compliant to extend an ungrounded circuit.
I've installed a csed
A meter socket is installed before the first over current protection device. This K&T circuit should be on a branch circuit protection device after both the CSED and OCPD so what does that have to do with your question?

The final answer to your question is you should not do it. You need to find a way to run new cable. Running conduit outside the house concealed as much as possible by burial or cable in enclosed soffits are two ways.
 
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Old 02-26-14, 10:24 AM
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Thank you guys!! So under California electric code you cannot extend knob and tube and the inspector will fail it?
 
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Old 02-26-14, 10:28 AM
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Yes.

.
 
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Old 02-26-14, 11:08 AM
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CSED - Combination Service Entrance Device. Also known as a meter-main http://www.schneider-electric.us/doc...eter-mains.pdf
 
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Old 02-26-14, 11:18 AM
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Thank you! kljvpdfjol-ds[fblp]a[dkmoujbvknapdf[gbp
 
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Old 02-26-14, 04:09 PM
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You can feed the existing knob and tube circuits from a new panel. Best way is to run a single cable from a double wied 240 volt breaker in the new panel to become the new feed for the old fused panel where the K&T begins.
 
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Old 02-27-14, 08:04 AM
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I thought NEC (section 390?) allowed splicing of K&T? I need to add about 2' to reach the new service panel. Is there anyway to do that under CA code?
 
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Old 02-27-14, 08:41 AM
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Ok, Inspector said I can splice K&T into romex a couple of feet to reach new service panel. Each K&T wire has to be in it's own junction box and then romex? Anyone understand/know the procedure on this? What if I can reach the panel with some of the K&T, can I run hot and neutral in one screw clamp through the panel box to the breaker? Thank you again!!!
 
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Old 02-27-14, 09:05 AM
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can I run hot and neutral in one screw clamp through the panel box to the breaker?
Yes but you need to put the wires in loom where they enter the clamp.
 
 

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